SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b891e10f8c376cebf087144a79a3bd7a195d45a66979bb79a14421274025dddf' 
  AND token = 'YPtVv5PiNQ5ca83atPA+TZ8DFogk4fcPgjlYEs03aw4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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