SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c134479dc75ed2519baa30518efacfa3e3cc19fc383a77af7b9f1d078802c184' 
  AND token = 'aHTDR32mMoSbILpsgejvQ7WyVNtTJblfwrlOcjoTM44=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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