SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4b2516723d7a55f9d24f2ff6a7ba92c41a2dedee8225d1fe98bcacf801bf3a9' 
  AND token = '579+yXi7IihueAN47/N1sdS6Bl3t0FOKLXhEIOdV2L4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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