SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b989cdee702f0d5a3948482801d66471af54d79571b9ca399ad978bb789e5905' 
  AND token = 'GXYCTVmPJIw7/V9taAMncjvM58jg6RKlOEbisoC3v04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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