SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5364758bce4391f3bfd1adccb0f57cd62a78672fb1e47012dd25c628e456f4fd' 
  AND token = 'xXAKM+VfgEZNT/KOuQdktzVPoTG1sllDkXZT6Cty/3Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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