SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90a5b6dbe6ad8a40dc1877bf553e9d04ec5581d4344d24d2a4e2b5818495d009' 
  AND token = 'YY/gKafMdZ6mBfFVUvsqO6cwqhQcD7URBSRMFmCn5RA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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