SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57ac4158cdd962eb2edbcc283e244484d0e8eb6b45bd0f42cd494dcd783b3c2d' 
  AND token = 'NFNXYixBlHumsvM34MYsKDOwaqZXX3UVPbr3sNxIQAg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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