SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bd37e2995fe4a7802eafe11e37b432ceeb7f7ba42ba2bf4b16ca681e17b48712' 
  AND token = '+uPEXL3jcvSWqNvpJKsQ2sYrqEhlQ6L/7WuFzzbcDXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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