SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b4923ff15d9c756c2e20bb6217116a0cda49f60a195a34b1c014d6d9d90eae04' 
  AND token = 'fYo8o97efjG2rHN1dVIrbuPlvX9MAk7OzMjc+rnd5wY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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