SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '979c3f0082bbc28e21127580b4c002d1e7b15875286d72369b41a51f8a8c546b' 
  AND token = '/FQ9dRUQ1nnDJXTLLdhRRn+TF6OZOXw2zIVImWuHp8g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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