SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c82ae3d11b8f6050b0a45eabcbeada3b9819df738e4d0e445a2491f0543877e' 
  AND token = 'LDzNiLR01af7TBp/ZGrWYhEEENMSAYkEG/UmMiGSKDU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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