SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0f589fb5a616e89836a465793d46d3eb64fb971fba2c9bad751c50838ac14fc' 
  AND token = 'YwXPKml5ajbuLPlWnR40azmjhv5L/HWUljJikIlhz2c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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