SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e7549b0893d2f92769932911bf33cebd33fa760dea2a5cfd03041cae1896497' 
  AND token = 'ZuDgiFPzUv0IDqS7+lBvhffvGjZTy7jtR4mPl7XENsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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