SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf0a1ff60fd6b199249431d2de10f9d64b81f683b75c47efa33ad9d69c52b7ed' 
  AND token = 'w6xyOVhPjpIGkHVv9OgNeP9Np6V7+hPacL8U/dYJk8Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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