SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9eb1ac1e25c9578264f1b6853fee7c2a5805d835496838c889da80c1b1765079' 
  AND token = 'hQPLXQ8SQMho2HsOdQnXnwJOBFaRo60UOcq6Xnb/q7A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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