SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c996516ae7740f2582e2ad91213ca2055de65135ed85980994b5deeacf475ee5' 
  AND token = 'cW64MyOXfFfym3j/9rTDpRfDWBS0ng/kV/JPO5x7dyA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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