SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4930b0c21e703ed9b8ab13f51eb357c8bf1bcb1bcdf32f131a1cc3350dae860' 
  AND token = 'DqkONzDrmPPHl+8llJSVejuKAmwJ9VQgoE74aidHmRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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