SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78daf39d527324e66666dfad09d19fd7843f2225cb418183c859a51f9ae420f8' 
  AND token = 'WW5vh3cLH1JTo6fhikWAtOWUOw2gWm4ETXEHX9HmRyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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