SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e58a4bb9b98672fddacef963d1c198915f0fb2ceebd226d3d5e6b368755733b6' 
  AND token = 'irjM7mnlvuIQUdAvGqgH0aWvUVVRb+LA98ntnpLr3KI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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