SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3234464e177a92025b62c0d91c06d38c6d8d891cb1127c5091af2a77a73be63a' 
  AND token = 'WfkLwvLhjt8Z2utVDfJw/aVj+D6eKzCWP6EGlNOw4kY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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