SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '703e4c5934230745262be05c867dbd2bb7e3598b280f44966bcfcb6839023e73' 
  AND token = 'OUsTOjWcRUm/ldU918YqYhSn1U+tx9vxJqQjDlS29pM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}