SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '52ea24865d3acdd3f85148082bed697c6c600885d042caa2b4b060122485464a' 
  AND token = 'EH+dmGwyOwQQ7Ee7aEGJrgW/sAebmNUsEwpxs+KKvNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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