SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69c102adf50a988e75d0146809f8ca9f4d94f6921f065c2c981ae5444d391577' 
  AND token = 'rrYi1j0UXQj8OXFA+urOIRfTWvlGOPvLUN3uc8UZz8Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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