SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4051ab366f3c3b5169f03fba7454f733f90657f6bb17dea101be61be2403e7a0' 
  AND token = 'PVHCvn4bNZDVKXlHDvnPZm7CptfwdCJLfu/iwj4rwQY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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