SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '27bd6886f79052806cecf5faf9e784c67326671e4d8057884a670a83495e8fcf' 
  AND token = 'KTkwbqY/POlQhwQVN56XweVp8wsZiFdtP4SjGDPBgHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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