SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c6feaea980ebc8275a4dd8d6234446369cb76e5d693e7d491c8643e9e854ab7a' 
  AND token = '3hNoJJ7nDv/vJbo5u/F8Uv+M5JOKYCDeX5iT3pdT3Ys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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