SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90bd968de239f60da9182a51299e4c72f1f0aec29fe3fdedafe6e3d16291ca16' 
  AND token = 'uROhzKPITs/N65qwOmGDR2/7wiaJbsOHN4h0sawDJcc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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