SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95f56eaa66c7a078567ee688425a773cd3f19cba7c662a497647d16467e5806b' 
  AND token = 'L4T+wwZQovihwMUzLGcyRLnz1J8xUWRrCLujHL188wg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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