SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '962fa638e9cb70fc95523baa72f93b97607141248d2fc99ceceb3ca88b6e28e6' 
  AND token = 'wIydR7in1BRbfeYQj4mWpWz+RZgiocPJNpk1oY5KCno=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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