SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38ab7792d32cebefa9698dee2308abf4a437b4fbf7a2cc36ba67172c9a74bd1b' 
  AND token = 'WOLC92LW0zGbMSRxhwY87RJ2+YBjZqnCTHq3R7fov/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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