SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0bb5f74cfa88bec8fa43eb35feed7d7dad33db170293c280905a6d6be23fc8b' 
  AND token = 'd9rSROutcpvmJwI6sP8HMnkQVeHJMkkNuXgMfhx1Wys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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