SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ab87d631e2c106a9cdf1c8d0ebf000a0a8066249199101daf232b98965d8bb4' 
  AND token = 'oRxmbuOadAXGv1/woxeOgG2wmR0kDxcHs0Oa+I2s0bU=' 
  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"
    }
  }
}