SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1df1c40ec388d208aa1116147dfd13da1ff0b2f7bf9af45056cd8e57d5615ecd' 
  AND token = 'aWfGd+m4RduscTJZZOJCv2ijwJ+Y/wzvUYTPd2qgT6Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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