SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6957a5e3a0f19a90e0d1d19b0cdfb43141bb4bff4fd7152a82024c93997fb8a1' 
  AND token = 'WSGWZHk0Fnv/6ZejSUQfyYGQHxozbdvaqlLuKr+asZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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