SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '96b8be937d42b57ecb569034c063e81f20ebd203743662c9bbd0a863188e63af' 
  AND token = 'xbv6zrYOtF4+b/eE9zelkClEWtwJhY6CYHxQ72eKjWY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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