SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4462496c728ce62984ff784a5e54b94c58ac9967ab713d033dc5b0bf0f638012' 
  AND token = 'c+d5VJZ8lfjbvC6uUa9MBRzXhOzd/SAPqiNJtTQkFTE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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