SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26483f89e221c118572f02e30b2d368bac675f91db2d058e367a3ea3dfae9539' 
  AND token = 'FAYY9/wm5yEzuf0JcLnOhPryceMRBQGTWAmg8S4VcZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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