SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f06b02d021bd8899b428d84bbda04cbeb9cc7451a87587043167629b29ffdadd' 
  AND token = 'X16SDeTT9g4JsesBjjhnA31kmZKv6JB9JpDUFq/QvUY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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