SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fbf6519d935fb65bbeea60e48850f13220d038c653f61f0f61aa5420489562b7' 
  AND token = 'HlUFhk6TuSNER14qbhglSa55+upZbFlpDgDipfkAMUw=' 
  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"
    }
  }
}