SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '74e9097df767cc80eb95bf9876706c0b76cbfdbd092947dd98b81d99bd031756' 
  AND token = '7HvuJH4i/jgrzQ6r+zF2u5lh3IlZSN+e3qBapAGdp+k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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