SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '35025f4c648550b17c89bf862f84dbc6bab6bf124584c340bb2a0bc7ae20a92a' 
  AND token = 'PdU/A9AQ/UW/IwFJ7dEpM7KlC6TrhpxZlbVGH2BD3D8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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