SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2669a120f9d8e2c7c665d95b306ddc621c967ad46e56e1a21a131afe3cc6a1ab' 
  AND token = 'ZMBcKdJJLduQmNpWEvjttPxuDvJtwuaCpskDw7AUYao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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