SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f6faa2408dfcce0132da5b8213c6f25c8766f2503f5ade3144126209380396ff' 
  AND token = 'Go7Nus4GWQHuPURXaVUzhm2T+KtDakbzzgHN5wOBnqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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