SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3357037317ad09f55d7cf426ff189e785cd32010f26dc614ea6e98f6818d33ab' 
  AND token = 'flbNX+6oLp9Pk7KQLhSWeEvwxSBEUQsmohDy0zLtn2U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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