SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1be1fe7bb76152257844e7982ec5bdecb6df42359d9ede2b5238d378d9f8564c' 
  AND token = 'evdGmbkyQFEpjxJQqebHapUWr39v69CX46SA+OehWRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00179

JSON explain

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