SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60c7943d24922326d11378840a02983d1df9e64bfecb96946a70bc05e3d18079' 
  AND token = '7QN3BKJYSYNs4NldtnECYf2uQ5MV9GPFx6KIa9xWiwQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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