SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3fec5e1c5ae4f1795e1dc784318feb953c532b2fb8dd363b450dcd19b45967a' 
  AND token = '3rj20OAJ0Em966BsNKeAr5yasRHbG/lYsnhKbXS29FI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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