SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88b22181efbdfeab8ad90cfcf1c74570aa6d878e17af04c8da4961ad7cef7ce1' 
  AND token = 'TrTz+3IYFcY9SKrLRry3JkZLiKTNMRdtDFvsZlPXq1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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