SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90d2d3291d0b7ae6cd92ca8c370a3d127cbe2155fac882b3d5f74b7df0dcd729' 
  AND token = 'KPNPgYvgNNK9iVy0iQNpvRYdLiC3/Fjw+WOJBOkHq+0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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