SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c16cdf94f444e46928707408e08c2f558aae97ae6541b8a312357b9b7553641' 
  AND token = 'IFfYGzwY80XThBFqHZQdiwogJSxd8+lf6pN1W4e6S58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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