SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1ae0db49511aff638307a538caea2f64d3ee0d2c22a4ec08ef123feaa28aa6f' 
  AND token = 'KHY5gLNUUJo7hZpsZKCHKw/twjKW6427jmbQfsYBGZE=' 
  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"
    }
  }
}