SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cecfa242fb243b68f2248209d0f733c7c39510a144fda5ffcd55edaaeba49a8d' 
  AND token = 'gKO5ZHJeyqIq/UB+/sGhotxG2Du/JrGwDLAqd9ar4pI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}