SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5458f3e7b34395a4449dd51b3790db9eafaf3c0294163ff93f3e9581dcad0c7d' 
  AND token = 'f18xHhvYJqfvmga/uEN0wrF/A3uwP1Rt06TgTcgk8Is=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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