SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '837f70ae9a088787dd0cd761138cffe51569709543c7f12f4ada53fc55efc3b6' 
  AND token = 'EHIgXFUYkb34qLVR8hC9u9nU+b172emxl64ag6Xu8RA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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