SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b91694663b15fff9f6119b5851afc85adc6ef223e3a6b4a6991bc2a09ba714b' 
  AND token = 'bzPLn3PNPMy6ElZJ7OUvCKNefj/KDNk7Ep34JivmOdg=' 
  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"
    }
  }
}