SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'deb1180f58b8f642a8477bf9817a119d9d95419cd4a0b2688e262ac4edc19bac' 
  AND token = 'XLkOXyPfUspG1clYzSdzRPU5vSp8W2cOiiZsoO7XLO8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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