SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fbaa1d5968bc0ffca3bbaf926ddbc4dbf2388db3f3079d57df01577e3338b66b' 
  AND token = 'iLYISNK4HTcOqmuDVkOuXmTFfTnTP3QIUDtZueywVwU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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