SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bc5b769b093078d8b260812efb12f10f706522b43b99e82f21893ddc4fdabf1a' 
  AND token = 'aTwxlNdIr9mFrALC2N2OpUWM/+wk6EwFBRoNqUr1m28=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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