SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac1ba696a542d86c103ccda87b94ef16dc9c5e6cf04f93230a2c0d1766d51280' 
  AND token = 'ZQGsGs9xFKe9UBhFglc/NI/E/taQ8VohRwoYM51uEUg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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