SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6779c385afe7750af0a9a1fc6dde6d69512219cd001dd0f506fd2cd4a3264a4d' 
  AND token = 'jRk9CbwCeUoPUuilFgEiClWlfcJBwb27dEf7LSksM24=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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