SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09198cf44ddaeef1ceeef65677ff0ef9e78a09809ad32882f45857a30068deb8' 
  AND token = 'X1LdsBejdw+rI+XBozrankvVMtTpiit1+gAxoZ9jePs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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