SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '954d76a99122573dbdcc68e842022b4c8b536a4d31273c7d72ee2683f5aef521' 
  AND token = 'Te5ijPhaDLBRFkFg9NyVpUvSeRaRQdsR5pFSU1keKvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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