SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08aac962ea1823cabaffd8bf0ce5b1eb313f8fd6dcbb3a46591cc68ae00b00f5' 
  AND token = 'JarclZ/38AzzqxA2o18IlEc8Sn9OrXB49t5KAN9jE7U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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