SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46e837461f0b5e3bb2da0f7577b074799bfde1fbcb509c6e4e039d4d78d65d92' 
  AND token = 'zOCOvBNfecopV/UdbmMSVCCxx1vVoHk5wgmdNbCxMso=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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