SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f92be205bd2985aac659e2258f32bbf00e5ea946158e333c3d0b9434598a7f6d' 
  AND token = 'juH22OdPZJ4fJzaqIXRuhKtsIMZ0QjR1CA1TvqhVCIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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