SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54412ac4ee074ecf2babb2a2133577f5c778e65ca76c1f1fb2c54c5f5d893309' 
  AND token = 'lIZBixX9lE3y3vEq7mUNVD9F6BX1rVeBeKjJRw3M3ls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}