SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd841e03e9afe450a26b69b34b15409cbbd1ac0c07559510f681d25cd70f0a890' 
  AND token = 'bVtXrgxtU0MjmXd8tWeigt56t6LidlWuGKLBSyoqoJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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