SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1aa9b19f954fb530f386e0f1a6a0a4e921e463e5eba20965cf3260e92b7cb727' 
  AND token = 'GvPaK9kE+swWNslUPLSfqLAazIFD5ozPDgvfq2Rwe4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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