Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92b756ec35fa2e5171ca38612b43d3ba77492d554eba8a2a8ee6a4d2226c99e2' 
  AND token = '/DmUWMza6ZmZWT+rbubYMm1rBiyjJ8Tzd5wMgk5i4bQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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