SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ca799965035627438079d0663b051681af8bb617e60a368a503c0658273991f' 
  AND token = 'PaZCApZ7ywCFopCrG1BmrzhslwI62Z+Rju2q5nSjqfM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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