SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e57099491a4a38d6727076366075ae4df8ea40594a54776250f770d0838e483' 
  AND token = 'wQP+o9bIfdKXpk2jK2QFeRI0WNDiO/tVjGjISaNDKNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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