SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ffba8497c3eb2d70962216ada160bb4a2ce2ff33361e2c2bdaf5b7f97d09ba9' 
  AND token = 'A4vktEbQl0e3KgFq4EM+xoDjWNliFpo6nRmlCA89/80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}