SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec4e3574fa3730cfafdfde607245bd8a39599917e58fdbca16214ea2d42e885b' 
  AND token = '/fKQYNcnFDQZH/gTAa/mVJJX6vwr6twNq07iMPClR8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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