SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '059234c05261a5e14cf588eb691aefc9e94ef35bac287c0fb3407ccc69e56157' 
  AND token = 'WhGynDPrpdKZHePFPwfEf5Los9AtibzSuPEuZjRV7SA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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