SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'a6ba0a49f443b77983223257f816b72a05b9045f7a08bb0e0cf742803c96431a' 
  AND token = '7NT0Scoig161iv8DGyCDn02VDdLjJLV5lXkoBfYHJgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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