SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0c2b73d9d8516bd4c949af56cc2fc3d04e47b08e648a63bb90df480eaea5a93' 
  AND token = '2OMYFKdZsCL+FE7h0r2+st+XpG+Vh4FvWiBUhx2vGB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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