SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '319766d6ed361374b78dfe8b3e5a221aa3161e8babafc6b8cd06c5ab2ff68327' 
  AND token = 'rEvO4SkuPQdrcXRiAmOUfjiSZ0L1l7z6c3dDbZrKwqo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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